Activated carbon from coconut shells (ACCS) was synthesised and used for the removal of metal ions (manganese, iron, nickel and copper) from aqueous solutions. Two different adsorption models were used for analysing the data. Adsorption capacities were determined: copper ions exhibited the greatest adsorption on activated carbon obtained from coconut shells because of their size and pH conditions. Adsorption capacity varied as a function of the pH. Adsorption isotherms from aqueous solutions of heavy metals on ACCS were determined and were found to be consistent with Langmuir's adsorption model. Adsorbent quantity and immersion enthalpy were studied. The results were compared with other adsorbents used in a prior study.

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Copper nanoparticles within the pore channels of selectively grafted mesoporous silica SBA-15 were synthesized. Silanols on the external surface of as-SBA-15 were first capped by ÀSi(CH 3 ) 3 groups. After the removal of the template of capped SBA-15 by calcination, silanols on the internal surface of SBA-15 were modified by 3-aminopropyltrimethoxysilane (APTMS), and then formaldehyde was grafted to the amino groups of APTMS and with Cu(NH 3 ) 4 (NO 3 ). The support and catalyst were characterized by X-ray diffraction (XRD), BarettÀJoynerÀHalenda (BJH) pore-size distribution, BrunauerÀEmmettÀTeller (BET) surface area, Fourier transform infrared spectroscopy (FT-IR), transmission electron microscopy (TEM), scanning electron microscopy (SEM), and adsorption calorimetry. The initial conversion follows the trend in size: 52 % at pore size 6.0 for this catalyst at 343 K.

Copper, palladium and iridium nanoparticles were synthesised within the pore channels of selectively grafted mesoporous silica SBA-15. The support and catalysts were characterised by different techniques. The synthesized catalyst were able to catalyse oxidation of carbon monoxide with activity values as high as 7.0 9 10 -3 mmol g -1 cat s -1 at 353 K. Carbon monoxide conversion was found to increase with decreasing nano particle size.

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An adsorption microcalorimeter for the simultaneous determination of the differential heat of adsorption and the adsorption isotherm for gas-solid systems are designed, built, and tested. For this purpose, a Calvet heat-conducting microcalorimeter is developed and is connected to a gas volumetric unit built in stainless steel to record adsorption isotherms. The microcalorimeter is electrically calibrated to establish its sensitivity and reproducibility, obtaining K=154.34±0.23 WV−1. The adsorption microcalorimeter is used to obtain adsorption isotherms and the corresponding differential heats for the adsorption of CO2 on a reference solid, such as a NaZSM-5 type zeolite. Results for the behavior of this system are compared with those obtained with commercial equipment and with other studies in the literature.

Techniques such as adsorption microcalorimetry and the dehydrogenation of alkenes are used to measure the differential heats of adsorption and reactivity of several catalyst surfaces. An adsorption microcalorimeter built specifically to determine adsorption heats is employed. CO was used as the probe molecule in this study and was adsorbed on the following catalysts: Pd/mordenite, Pd-Pt/ mordenite, and Pd-Ir/mordenite. The results show that the differential heat of adsorption was between 50 and 150 kJ/ mol. The adsorption heat decreases with an increased in CO coverage for all catalysts. The best conversion for alkene studies was seen on the Pd-Ir/mordenite, which was close to 70%.

The zeolites HZSM5 and HMOR were synthesized and their behavior analyzed during the conversion from methanol to propylene (MTP). These zeolites were studied with XRD, SEM, NH 3 -TPD, nitrogen adsorption at 77 K and adsorption microcalorimetry. It was established that acidity infl uences the conversion of methanol to propylene. The development of mesopores in HMOR allowed the process to be more selective for MTP process. The role that acid and basic sites and the ratio Si/Al play in the conversion process was determined.